The experiments are CPMG at 750 Mhz and 600 Mhz. i have followed the tutorial: http://wiki.nmr-relax.com/Tutorial_for_Relaxation_dispersion_analysis_cpmg_fixed_time_recorded_on_varian_as_fid_interleaved for each experiment separately, which works fine. Now i want to analyse the experiments together to improve the fits on each residue. I have tried to merge the ncyc.txt and peaks_list_max_dx1_dy1.ser from each spectrum and run relax but i cant make that work. hope you can help Jens